Brian Cryer's Web Resources

Brian Cryer's Glossary of IT Terms with Links


A boundary formed by equal travel times from a point.

An isochrone is a polygon, generated around a point where the travel time to each point on the polygon is identical.

In an open field, a 5 minute walk-time isochrone should be a circle because a person should be able to walk 5 minutes in any direction. In a built up urban area it will be an odd shape following roads and building outlines because routes are obstructed.